1. Field
Example embodiments relate to a resistive memory device and method for programming a resistance conversion layer, for example, the resistive memory device and method may stabilize a dispersion of voltages in the resistive memory device.
2. Description of the Related Art
Conventional resistive random access memories (RRAMs) may include a transition metal oxide as a data storage layer. The transition metal oxide may include a resistance changing property, which may be a resistance value that changes according to an applied voltage. The conventional RRAM may include a 1S (switch)-1R (resistance) structure having a switching structure, and a resistance conversion layer. The switch may include a diode, a transistor, or a varistor. The resistance conversion layer may include a transition metal oxide. The transition metal oxide may include a Ni oxide material, a Ti oxide material, a Cu oxide material, or a Co oxide material, for example.
A conventional method for programming a conventional RRAM is described below. A first electric pulse may be applied to the resistance conversion layer in order to program the RRAM to be in a set state. Accordingly, a current path, through which electric current flows, may be formed in the resistance conversion layer. Therefore, a resistance of the resistance conversion layer may become low. In addition, a second electric pulse may be applied to the RRAM in order to program the RRAM to be in a reset state. Accordingly, the current path in the resistance conversion layer may be removed, and the resistance of the resistance conversion layer may increase. In the conventional RRAM, a single pulse may be used in a programming operation. However, in an array structure of the RRAM, because not all of the resistances of memory cells in the set states and the reset states are equal to each other, some of the memory cells may not operate or operate normally.